1. Field
An aspect of the present invention relates to a pixel, and more particularly, to a pixel capable of finely controlling the amount of current and increasing the voltage range of a data signal.
2. Description of the Related Art
Recently, there have been developed various types of flat panel display devices capable of reducing the weight and volume of cathode ray tubes, which are disadvantages. The flat panel display devices include a liquid crystal display, a field emission display, a plasma display panel, an organic light emitting display, and the like.
Among these flat panel display devices, the organic light emitting display displays images using organic light emitting diodes that emit light through recombination of electrons and holes. The organic light emitting display has a fast response speed and is driven with low power consumption. A conventional organic light emitting display supplies current corresponding to a data signal to an organic light emitting diode using a transistor formed in each pixel, so that light is emitted from the organic light emitting diode.
The conventional organic light emitting display includes a data driver for supplying a data signal to data lines, a scan driver for sequentially supplying a scan signal to scan lines, and a pixel unit having a plurality of pixels coupled to the scan and data lines.
When the scan signal is supplied to a scan line, pixels included in the pixel unit are selected to receive the data signal from a data line. The pixels that receive the data signal display an image while emitting light with predetermined luminance corresponding to the data signal.
Meanwhile, the data signal is supplied to have a predetermined voltage range corresponding to desired luminance. In the organic light emitting display in which the pixel controls micro-current, the data signal is necessarily set to a narrow voltage range corresponding to the micro-current. However, there is a limitation in lowering the voltage range of the data signal due to an error of a digital-to-analog converter (DAC) included in the data driver, or the like.
The conventional pixel controls the amount of current using a voltage between gate and source electrodes of the driving transistor. However, in a case where the voltage between the gate and source electrodes of the driving transistor in the conventional pixel, it is difficult to finely control the amount of current.